From 8665bd53f2f2e27e5511d90428cb3f60e6d0ce15 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 20:50:12 +0200 Subject: Merging upstream version 6.8.9. Signed-off-by: Daniel Baumann --- net/sched/act_api.c | 251 ++++++++++++++++++++++++++++++++++------------------ 1 file changed, 163 insertions(+), 88 deletions(-) (limited to 'net/sched/act_api.c') diff --git a/net/sched/act_api.c b/net/sched/act_api.c index c39252d61..3e30d7260 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -816,6 +816,9 @@ EXPORT_SYMBOL(tcf_idr_cleanup); * its reference and bind counters, and return 1. Otherwise insert temporary * error pointer (to prevent concurrent users from inserting actions with same * index) and return 0. + * + * May return -EAGAIN for binding actions in case of a parallel add/delete on + * the requested index. */ int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, @@ -824,43 +827,61 @@ int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, struct tcf_idrinfo *idrinfo = tn->idrinfo; struct tc_action *p; int ret; + u32 max; -again: - mutex_lock(&idrinfo->lock); if (*index) { +again: + rcu_read_lock(); p = idr_find(&idrinfo->action_idr, *index); + if (IS_ERR(p)) { /* This means that another process allocated * index but did not assign the pointer yet. */ - mutex_unlock(&idrinfo->lock); + rcu_read_unlock(); goto again; } - if (p) { - refcount_inc(&p->tcfa_refcnt); - if (bind) - atomic_inc(&p->tcfa_bindcnt); - *a = p; - ret = 1; - } else { - *a = NULL; - ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, - *index, GFP_KERNEL); - if (!ret) - idr_replace(&idrinfo->action_idr, - ERR_PTR(-EBUSY), *index); + if (!p) { + /* Empty slot, try to allocate it */ + max = *index; + rcu_read_unlock(); + goto new; + } + + if (!refcount_inc_not_zero(&p->tcfa_refcnt)) { + /* Action was deleted in parallel */ + rcu_read_unlock(); + return -EAGAIN; } + + if (bind) + atomic_inc(&p->tcfa_bindcnt); + *a = p; + + rcu_read_unlock(); + + return 1; } else { + /* Find a slot */ *index = 1; - *a = NULL; - ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, - UINT_MAX, GFP_KERNEL); - if (!ret) - idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY), - *index); + max = UINT_MAX; } + +new: + *a = NULL; + + mutex_lock(&idrinfo->lock); + ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max, + GFP_KERNEL); mutex_unlock(&idrinfo->lock); + + /* N binds raced for action allocation, + * retry for all the ones that failed. + */ + if (ret == -ENOSPC && *index == max) + ret = -EAGAIN; + return ret; } EXPORT_SYMBOL(tcf_idr_check_alloc); @@ -1098,7 +1119,8 @@ repeat: } } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) { if (unlikely(!rcu_access_pointer(a->goto_chain))) { - tcf_set_drop_reason(res, SKB_DROP_REASON_TC_ERROR); + tcf_set_drop_reason(skb, + SKB_DROP_REASON_TC_CHAIN_NOTFOUND); return TC_ACT_SHOT; } tcf_action_goto_chain_exec(a, res); @@ -1118,8 +1140,7 @@ int tcf_action_destroy(struct tc_action *actions[], int bind) struct tc_action *a; int ret = 0, i; - for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { - a = actions[i]; + tcf_act_for_each_action(i, a, actions) { actions[i] = NULL; ops = a->ops; ret = __tcf_idr_release(a, bind, true); @@ -1136,18 +1157,29 @@ static int tcf_action_put(struct tc_action *p) return __tcf_action_put(p, false); } -/* Put all actions in this array, skip those NULL's. */ static void tcf_action_put_many(struct tc_action *actions[]) { + struct tc_action *a; + int i; + + tcf_act_for_each_action(i, a, actions) { + const struct tc_action_ops *ops = a->ops; + if (tcf_action_put(a)) + module_put(ops->owner); + } +} + +static void tca_put_bound_many(struct tc_action *actions[], int init_res[]) +{ + struct tc_action *a; int i; - for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { - struct tc_action *a = actions[i]; - const struct tc_action_ops *ops; + tcf_act_for_each_action(i, a, actions) { + const struct tc_action_ops *ops = a->ops; - if (!a) + if (init_res[i] == ACT_P_CREATED) continue; - ops = a->ops; + if (tcf_action_put(a)) module_put(ops->owner); } @@ -1211,8 +1243,7 @@ int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[], int err = -EINVAL, i; struct nlattr *nest; - for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { - a = actions[i]; + tcf_act_for_each_action(i, a, actions) { nest = nla_nest_start_noflag(skb, i + 1); if (nest == NULL) goto nla_put_failure; @@ -1274,30 +1305,29 @@ static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = { [TCA_ACT_HW_STATS] = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY), }; -void tcf_idr_insert_many(struct tc_action *actions[]) +void tcf_idr_insert_many(struct tc_action *actions[], int init_res[]) { + struct tc_action *a; int i; - for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { - struct tc_action *a = actions[i]; + tcf_act_for_each_action(i, a, actions) { struct tcf_idrinfo *idrinfo; - if (!a) + if (init_res[i] == ACT_P_BOUND) continue; + idrinfo = a->idrinfo; mutex_lock(&idrinfo->lock); - /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if - * it is just created, otherwise this is just a nop. - */ + /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ idr_replace(&idrinfo->action_idr, a, a->tcfa_index); mutex_unlock(&idrinfo->lock); } } -struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police, - bool rtnl_held, +struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags, struct netlink_ext_ack *extack) { + bool police = flags & TCA_ACT_FLAGS_POLICE; struct nlattr *tb[TCA_ACT_MAX + 1]; struct tc_action_ops *a_o; char act_name[IFNAMSIZ]; @@ -1329,6 +1359,8 @@ struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police, a_o = tc_lookup_action_n(act_name); if (a_o == NULL) { #ifdef CONFIG_MODULES + bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL); + if (rtnl_held) rtnl_unlock(); request_module("act_%s", act_name); @@ -1445,9 +1477,7 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) { struct tc_action_ops *a_o; - a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE, - !(flags & TCA_ACT_FLAGS_NO_RTNL), - extack); + a_o = tc_action_load_ops(tb[i], flags, extack); if (IS_ERR(a_o)) { err = PTR_ERR(a_o); goto err_mod; @@ -1488,7 +1518,7 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, /* We have to commit them all together, because if any error happened in * between, we could not handle the failure gracefully. */ - tcf_idr_insert_many(actions); + tcf_idr_insert_many(actions, init_res); *attr_size = tcf_action_full_attrs_size(sz); err = i - 1; @@ -1497,10 +1527,8 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, err: tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND); err_mod: - for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { - if (ops[i]) - module_put(ops[i]->owner); - } + for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++) + module_put(ops[i]->owner); return err; } @@ -1753,10 +1781,10 @@ err_out: static int tcf_action_delete(struct net *net, struct tc_action *actions[]) { + struct tc_action *a; int i; - for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { - struct tc_action *a = actions[i]; + tcf_act_for_each_action(i, a, actions) { const struct tc_action_ops *ops = a->ops; /* Actions can be deleted concurrently so we must save their * type and id to search again after reference is released. @@ -1768,7 +1796,7 @@ static int tcf_action_delete(struct net *net, struct tc_action *actions[]) if (tcf_action_put(a)) { /* last reference, action was deleted concurrently */ module_put(ops->owner); - } else { + } else { int ret; /* now do the delete */ @@ -1780,31 +1808,45 @@ static int tcf_action_delete(struct net *net, struct tc_action *actions[]) return 0; } -static int -tcf_reoffload_del_notify(struct net *net, struct tc_action *action) +static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net, + struct tc_action *action) { size_t attr_size = tcf_action_fill_size(action); struct tc_action *actions[TCA_ACT_MAX_PRIO] = { [0] = action, }; - const struct tc_action_ops *ops = action->ops; struct sk_buff *skb; - int ret; - skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size, - GFP_KERNEL); + skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL); if (!skb) - return -ENOBUFS; + return ERR_PTR(-ENOBUFS); if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) { kfree_skb(skb); - return -EINVAL; + return ERR_PTR(-EINVAL); + } + + return skb; +} + +static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action) +{ + const struct tc_action_ops *ops = action->ops; + struct sk_buff *skb; + int ret; + + if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) { + skb = NULL; + } else { + skb = tcf_reoffload_del_notify_msg(net, action); + if (IS_ERR(skb)) + return PTR_ERR(skb); } ret = tcf_idr_release_unsafe(action); if (ret == ACT_P_DELETED) { module_put(ops->owner); - ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0); + ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0); } else { kfree_skb(skb); } @@ -1870,23 +1912,41 @@ int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb, return 0; } -static int -tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[], - u32 portid, size_t attr_size, struct netlink_ext_ack *extack) +static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n, + struct tc_action *actions[], + u32 portid, size_t attr_size, + struct netlink_ext_ack *extack) { - int ret; struct sk_buff *skb; - skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size, - GFP_KERNEL); + skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL); if (!skb) - return -ENOBUFS; + return ERR_PTR(-ENOBUFS); if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION, 0, 2, extack) <= 0) { NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes"); kfree_skb(skb); - return -EINVAL; + return ERR_PTR(-EINVAL); + } + + return skb; +} + +static int tcf_del_notify(struct net *net, struct nlmsghdr *n, + struct tc_action *actions[], u32 portid, + size_t attr_size, struct netlink_ext_ack *extack) +{ + struct sk_buff *skb; + int ret; + + if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) { + skb = NULL; + } else { + skb = tcf_del_notify_msg(net, n, actions, portid, attr_size, + extack); + if (IS_ERR(skb)) + return PTR_ERR(skb); } /* now do the delete */ @@ -1897,9 +1957,8 @@ tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[], return ret; } - ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC, - n->nlmsg_flags & NLM_F_ECHO); - return ret; + return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC, + n->nlmsg_flags & NLM_F_ECHO); } static int @@ -1950,26 +2009,44 @@ err: return ret; } -static int -tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[], - u32 portid, size_t attr_size, struct netlink_ext_ack *extack) +static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n, + struct tc_action *actions[], + u32 portid, size_t attr_size, + struct netlink_ext_ack *extack) { struct sk_buff *skb; - skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size, - GFP_KERNEL); + skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL); if (!skb) - return -ENOBUFS; + return ERR_PTR(-ENOBUFS); if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags, RTM_NEWACTION, 0, 0, extack) <= 0) { NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action"); kfree_skb(skb); - return -EINVAL; + return ERR_PTR(-EINVAL); } - return rtnetlink_send(skb, net, portid, RTNLGRP_TC, - n->nlmsg_flags & NLM_F_ECHO); + return skb; +} + +static int tcf_add_notify(struct net *net, struct nlmsghdr *n, + struct tc_action *actions[], u32 portid, + size_t attr_size, struct netlink_ext_ack *extack) +{ + struct sk_buff *skb; + + if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) { + skb = NULL; + } else { + skb = tcf_add_notify_msg(net, n, actions, portid, attr_size, + extack); + if (IS_ERR(skb)) + return PTR_ERR(skb); + } + + return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC, + n->nlmsg_flags & NLM_F_ECHO); } static int tcf_action_add(struct net *net, struct nlattr *nla, @@ -1977,7 +2054,7 @@ static int tcf_action_add(struct net *net, struct nlattr *nla, struct netlink_ext_ack *extack) { size_t attr_size = 0; - int loop, ret, i; + int loop, ret; struct tc_action *actions[TCA_ACT_MAX_PRIO] = {}; int init_res[TCA_ACT_MAX_PRIO] = {}; @@ -1990,13 +2067,11 @@ static int tcf_action_add(struct net *net, struct nlattr *nla, if (ret < 0) return ret; + ret = tcf_add_notify(net, n, actions, portid, attr_size, extack); - /* only put existing actions */ - for (i = 0; i < TCA_ACT_MAX_PRIO; i++) - if (init_res[i] == ACT_P_CREATED) - actions[i] = NULL; - tcf_action_put_many(actions); + /* only put bound actions */ + tca_put_bound_many(actions, init_res); return ret; } -- cgit v1.2.3